Signaling system



Dec. 8, 1931;

Filed. Nov. 10, 1930 INVENTOR I REGI LD D.SALMON Patented Dec. 8, 1931 UNrI o STATES PATENT OFFICE REGINALD DENNIS SALMON, or GROYIDON, SURREY, ENGLAND, ASSIGNOR TO cnnnn AND COMPANY, LIMITED, or onoYDoN, SURREY, ENGLAND SIGNALING SYSTEM Application filed November 10, 1930, Serial No. 494,630, and in Great Britain January 22, 1930.

This invention relates to signaling systems in which currents transmitted over a line circuit are employed to eflect the actuation of apparatus at a receiving station.

. Usually in such systems the signaling currentstransmitted over the line circuit are employed to control the actuation of the receiving apparatus, whilst the energy for actuating such apparatus is furnished by local sources.

According to the present invention, energy storing means is associated with the line circuit at a receiving station to store energy from the line currents which energy is sub sequently utilized for actuating apparatus under control of signaling currents. v

In many signaling systems in which the apparatus at a receivingstation is not of a very heavy nature or construction such as to require considerable power for its actuation, and particularly in systems in which signaling is not continuous or in'which pauses of greater or less duration occur between the intervals of signaling, considerable advantages can be obtained by thus storing energy received over aline circuit. This energy may be utilized to efiect operations which although occurring infrequently during sig naling, require a relatively considerable consumption of energy. By this means, the actuation of receiving apparatus can be effected either solely or mainly by energy received over the line circuit in cases where the energy would be insuificient to effect the actuation direct.

According to one feature of the present invention, in a signaling system which operates on signaling currents separated by inter- Vals of direct current, electromotor means connected to the line circuit is adapted to wind up energy storing means such as a spring or a weight for actuating apparatus under control of the signaling currents. The electromotor means, as will hereinafter appear, can be arranged so that other means connected to the line circuit for controlling apparatus is responsive to signaling currents, whilst the electromotor means is operative chiefly during the intervals of direct current between the signaling currents.

According to another feature of the present invention, in a signaling system which operates on signaling currents comprising trains of current impulses, condenser means is connected to the line circuit, adapted to I be charged during said trains of impulses, and discharged through electromagnetic means for actuating printer function devices. In systems wherein the current impulses are composed of current reversals, the condenser energy storing means may advantageously consist of two condensers charged duringthe trains of reversals either through current rectifying elements or through a contact tongue operated by means responsive to the signaling reversals.

According to another feature, a stock ticker or like telegraph system operating on trains of current impulses separated by intervals of direct current is arranged with electromotor means actuated chiefly during the intervals of direct current and subsequently effecting certain printer functions such as rotating a type wheel, and with condenser energy storing means charged during the trains or reversals for effecting other printer function such as the printing impulse following the selection of a printing character.

It will be understood that in order to utilize to the best advantage the relatively small amount of energy which can be obtained from a line circuit in a signaling system all mechanical losses shouldbe avoided as far as possible by reducing the weight of the moving parts to the minimum and by providing ball-bearings and like anti-friction devices to such moving parts. If this is not done, it will readily be seen that frictional and other losses may easily absorb all the surplus en-' ergy from the line circuit, leaving none available for the actuation of the printer functions for which it was intended.

The invention is hereinafter described as applied to a stock ticker or like telegraph system, which operates on a step-by-step code, this being a particularly advantageous application of the invention in which the necessity for providing local sources of power at a receiving station can be reduced or obviated entirely. The system thus becomes or approximates to a central energy system, the advantages of which are well known.

The accompanying drawings show the manner in which energy storing means according to the invention can be connected to a line circuit at a receiving station of a stock ticker or like telegraph system in which the signaling currents are composed of trains of current reversals separated by intervals of direct current. Fig. 1 is illustrative of the various features of the present invention, whilst Fig. 2 shows an alternative to a feature described with reference to Fig. 1.

Referring to Fig. 1, a polarized relay PR is connected between line L and earth E and is responsive to reversals of line current in each signaling train. This relay PR may control the escapement of a rotatable type wheel for selecting one of a plurality of printing characters in accordance with the number of impulses or reversals in the signaling train in any manner already well known. A capacity constituted by condenser K is connected between this relay PR and line L which capacity does not affect the operation of relay PR during reversals but serves to divert the direct current between trains of reversals from flowing in this part of the circuit. A small condenser PRK can be connected as shown across the winding of relay PR to assist the relay in responding to current reversals.

Connected to the line circuit in parallel with relay PR and condenser K is a small series wound motor SM. In series with mo tor SM is shown the winding of a nonpolarized relay NPR. This relay NPR is preferably copper capped or slugged in known manner to render it sluggish and nonresponsive to current reversals. During reversals, relay NPR does not operate, but on the intervals of direct current between trains of reversals, its armature operates and serves to control a printing impulse after the selection of a printing character by polarized relay PR. Series wound motor SM may be of the type employed in direct current integrating meters and is employed to store energy by winding a spring or lifting a weight through suitable clockwork gearing. Friction losses are avoided as far as possible, as previously mentioned by reducing the weight of moving parts to a minimum and mounting such parts on ball-bearings or the like.

It is not essential that the relays and motor should be arranged precisely as so far described, but this arrangement forms a convenient means in systems of the kind referred to whereby relay PR controls the selection of a printing character, relay NPR controls the printing impulses after selection has been made, whilst energy for actuating these printing functions as thus controlled may be supplied by that stored in the spring wound, or the weight lifted by motor SM. During signal current reversals, motor SM may slow down or stop, but being series wound, does not reverse. In the intervals of direct current between these trains of reversals, condenser K prevents the line current flowing direct through relay PR and thus shunting motor SM. The line circuit, therefore, passes through motor SM. A resistance HR of a convenient high value may be connected as shown between the junction of PR and K on one side and the junction line of NPR and SM on the other, in order to provide a small holding current for polarized relay PR during the intervals of direct current. This holding current, it will be noticed, however, does not shunt the current flowing through motor SM during signaling pauses.

Means is also shown in Fig. 1 whereby energy can be stored in condenser means dur ing the current reversals in a signaling train. Connected to the line circuit in parallel with relay PR and condenser K are two condensers A and B each connected to the earth side of the line circuit through current rectifying elements A1 and A2 respectively, the rectifying elements being preferably of the metal oxide type. The other sides of condensers A and B are commoned and connected through a suitable resistance SR to the line side of condenser K. This forms a charging circuit for the condensers A and B. A discharge circuit is formed for the two condensers A and B in series with the winding PM of a magnet and contacts 1 and 2 which may be controlled by the armature of a relay NPR above mentioned.

During current reversals, a portion of the line circuit is shunted through the charging circuit as described, the rectifier elements A1 and B2 being connected so that half cycles of current in one direction charge one condenser, the other half cycles of current in the other direction charging the other condenser. The resistance SR may be varied to limit the charging current to such a value that the condensers are charged during a period equal to a required minimum number of reversals. When the discharge circuit circuit is closed, in this case by contactsl and 2 of relay NPR, condensers A and B discharge in series through magnetic winding PM.

In a stock ticker printing telegraph, the energization of the magnet PM may conveniently be arranged to effect the actuation of a printing anvil. 'If desired, other printer functions, such as letter feed may also be effected by the actuation of this magnet.

Instead of charging condensers A and B alternately through current rectifying elements, the alternative arrangement shown in Fig. 2 may be employed. Condensers A and B are here shown connected to con-tact stops 3 and 4 between which a contact tongue 5 is actuated by the armature of polarized relay PR in response to current reversals. As in the previous case, condensers A and B are charged during reversals and discharged in series through a discharge circuit upon closure of this circuit.

Condenser PRK in this case serves as a phasing condenser so as to cause the moving tongue of the relay to pass from one contact stop to the other when zero current is flowing from the line.

It will be seen from the foregoing arrangements that by providing means to store energy from the line circuit during signaling reversals and also in the intervals of current between the signaling trains of reversals, sufficient energy can be obtained from the line circuit to actuate all the printing functions required in a page printing telegraph and thus render the ap-- paratus independent of local sources of power.

Although described as applied to a stock ticker or like printing telegraph system, it will be understood that the invention is applicable, as already stated, to other signaling systems. In many cas-es,,wherein signaling apparatus is at present actuated by local sources of power under control of line currents or directly by the line current itself, it may be found advantageous to arrange so that the line circuit fulfils the two functions of supplying energy for actuating the apparatus and for controlling this actuation through separate but co-acting means as will be apparent from the foregoing. The invention may be applied with particular advantage to signaling systems wherein the signaling apparatus are separated by relatively long idle periods. Energy can be stored cumulatively during these idle periods and utilized subsequently during signaling.

hat is claimed is:

1. In a signaling system, a line circuit apparatus controlling means responsive to signaling currents received thereover, and energy storing means associated with said line circuit to store electrical energy therefrom for actuating apparatus under control of said controlling means.

2. In a signaling system, a line circuit apparatus controlling means responsive to signaling currents received thereover, electromotor means connected to said line circuit and having a rotatable armature, and means for storing energy delivered through its rotatable armature by said electromotor means and for releasing said energy under control of said controlling means.

3. In a stock ticker or like telegraph system operating on a step-by-step code, a line circuit, printing apparatus, means responsive to signaling currents to control said printing apparatus, and energy storing means asso- .ciated with said line circuit to store electrical energy therefrom for actuating said apparatus. V

4-. In a stock ticker or like telegraph system, operating on signaling currents comprising trains of current reversals, a line circuit, condenser means connected thereto, means to charge said condenser means during trains of current reversals, electromagnetic means for effecting prmtmg functions, and means to discharge said condenser means through said electromagnetic means.

5. In a stock ticker or like telegraph system operating on signaling current comprising trains of current reversals, a line circuit, two condensers each disposed to be charged from said line circuit, rectifying elements disposed to permit one of said condensers to be charged positively and the other negatively during current reversals in said line circuit, electroe magnetic means and a discharge circuit for said condensers including said electromagnetic means in series therewith.

6. In a stock ticker or like telegraph system operating on signaling current comprisjunction of said two condensers of the individual rectifying elements, and electromagnetic means connected in said discharge circuit.

7. In a stock ticker or like telegraph system operating on signaling currents comprising trains of current reversals, a line circuit, a relay connected to said line circuit and responsive to current reversals, a series capacity associated with said relay in said line circuit, a contact tongue of said relay connected to a point of the line circuit on one side of said relay and capacity and movable between alternate contact stops, a separate condenser connected to each of said contact stops and at the same point to a discharge circuit, and electromagnetic means, in said discharge circuit the junction of said separate condensers being connected to a point of said line circuit on the other side of said relay and capacity to provide a charging circuit.

8. In a stock ticker or like telegraph sys tem operating on signaling currents comprising current reversals, the combinations as set forth in claim 5 and in which a resistance is included in the circuit in which said condensers are connected to the line circuit in order to limit the rate of charging during current reversals.

9. In a stock ticker or like telegraph system operating 011 signaling currents com- Jii prising current reversals, the combination as set forth in claim 6 and in. which a resistance is included in said charging circuit to limit the rate of charging of the condensers during current reversals.

10. In a stock ticker or like telegraph system, a relay responsive to current reversals and connected in series with a capacity in the line circuit, condenser means connected to the line circuit in parallel with said relay and capacity and adapted to be charged alternately during current reversals and electromotor means also connected to the line circuit in parallel with said relay and capacity, and means for storing energy delivered by said electromotor means.

11'. In a stock ticker or like telegraph sys tem, a polarized relay responsive to current reversals and connected in series with a capacity in the line circuit, a non-polarized relay responsive only to intervals of direct current between trains of current reversals series wound electromotor means connected in series with said non-polarized relay and connected together therewith in parallel with said polarized relay and capacity, a resistance connected between the junction of said polarized relay with said capacity and the junction of said electromotor means with said noirpolarized relay, the said resistance being dimensioned to pass a small holding current for said polarized relay during intervals of direct current.

12. In a stock ticker or like telegraph system, relay means responsive to current reversals in a line circuit, condenser means connected in parallel with said relay means and disposed to be cumulatively charged from said line circuit during current reversals, a separate discharge circuit for said condenser means, said discharge circuit including controlling contacts and electromagnet means for effecting printing functions, and a relay responsive only during intervals between trains of reversals for actuating said contacts in said discharge circuit.

In witness whereof I hereunto subscribe my namet'his twenty-third day of October, 1930.

REGINALD DENNIS SALMON. 

